The image of the electric vehicle (EV) as a golf cart is fading fast -- very fast, judging by the performance of one EV at the Pikes Peak International Hill Climb this summer.
Using an electric powertrain designed by AC Propulsion, the vehicle covered the 12.4 mile mountain course in 12 minutes and 20 seconds, placing 21st out of a field of 71 cars. It set a record for electric cars on that course, but, more significantly, it beat 49 other vehicles that used internal combustion engines.
"It opened people's minds to the possibility that electric vehicles are here," Josh Allan, vehicle engineer for AC Propulsion, told me. "We're trying to break down perceptions of electric vehicles as golf carts. This shows that they can offer high performance."
Indeed, the vehicle, designed by Summit Motorsports and sponsored by tire maker Yokohama, proved that electric vehicles can go head-to-head with gasoline-burning racecars. The vehicle started at a 9,390ft elevation and traversed 156 turns to reach the Pike's Peak finish line at 14,110ft. During that time, it averaged approximately 60mph.
Surprisingly, AC Propulsion engineers achieved all that with a modicum of special features. The powertrain, which included a 200kW AC induction motor and a power electronics unit, was fitted with special slots and a patented fin technology to help direct air inside the motor's housing and cool the rotor.
"With a conventional electric car on a highway, you're running at about 10 percent of the motor's capacity," Allan said. "But when you run it for 14 minutes at high sustained power, you need to find some way to extract the heat."
The Yokohama EV defeated the race's only other electric car, a Nissan Leaf. It employed a lithium-ion battery pack from Sanyo.
AC Propulsion's electric powertrain was not the first to turn in stunning race times. Electric cars have competed at drag strips for more than a decade, with many turning in stunning quarter-mile times.
Racer John "Plasma Boy
" Wayland, for example, has pushed his street legal White Zombie electric Datsun to quarter-mile times of 11 seconds. Bill Dube, founder of the KillaCycle
racing team, owns an electric motorcycle that has covered a quarter-mile in less than eight seconds. These teams and others have achieved such impressive race times by packing their vehicles with 900lb of batteries, and generating about 1,600A of current. As a result, the vehicles have beaten 450hp Dodge Vipers at drag strips.
Allan said a big part of the success of electrics in racing is the immediate torque the powertrain provides.
"Gas cars have to wait for their motors to spool up into that maximum torque region," Allan said. "In that respect, electric cars have an advantage. The torque is right there when you need it."